cyckV4

762 NON-OBVIOUSNESS
contaminating said product with said gel and without
substantially degrading said gel.
8. The process of claim 1 further comprising removing said rigid gel
from said dead volume by contacting said gel with a chemical agent
which substantially degrades said gel to a flowing solution.
11. The process of claim 1 wherein said gelation solution further
comprises an aqueous liquid contaminant present in said dead volume
which dissolves in said solution when said solution is placed in said dead
volume.
Two prior art references were applied against the claims on appeal. They were U.S.
Patent 4,664,294 (Hetherington), which discloses an apparatus for displacing dead space
liquid using impervious bladders, or large bags, formed with flexible membranes; and U.S.
Patent 4,683,949 (Sydansk), also assigned to Clay’s assignee, Marathon Oil Company,
which discloses a process for reducing the permeability of hydrocarbon-bearing formations
and thus improving oil production, using a gel similar to that in Clay’s invention.
The Board agreed with the examiner that, although neither reference alone
describes Clay’s invention, Hetherington and Sydansk combined support a conclusion of
obviousness. It held that one skilled in the art would glean from Hetherington that Clay’s
invention “was appreciated in the prior art and solutions to that problem generally
involved filling the dead space with something.”
The Board also held that Sydansk would have provided one skilled in the art with
information that a gelation system would have been impervious to hydrocarbons once the
system gelled. The Board combined the references, finding that the “cavities” filled by
Sydansk are sufficiently similar to the “volume or void space” being filled by Hetherington
for one of ordinary skill to have recognized the applicability of the gel to Hetherington.
DISCUSSION
The issue presented in this appeal is whether the Board’s conclusion was correct
that Clay’s invention would have been obvious from the combined teachings of
Hetherington and Sydansk. Although this conclusion is one of law, such determinations
are made against a background of several factual inquiries, one of which is the scope and
content of the prior art. Graham v. John Deere Co., 383 U.S. 1, 17, (1966).
A prerequisite to making this finding is determining what is “prior art,” in order to
consider whether “the differences between the subject matter sought to be patented and
the prior art are such that the subject matter as a whole would have been obvious at the
time the invention was made to a person having ordinary skill in the art.” 35 U.S.C.
§ 103. Although § 103 does not, by its terms, define the “art to which [the] subject matter
[sought to be patented] pertains,” this determination is frequently couched in terms of
whether the art is analogous or not, i.e., whether the art is “too remote to be treated as
prior art.” In re Sovish, 769 F.2d 738, 741, 226 USPQ 771, 773 (Fed. Cir. 1985).
Clay argues that the claims at issue were improperly rejected over Hetherington
and Sydansk, because Sydansk is nonanalogous art. Whether a reference in the prior art
is “analogous” is a fact question Thus, we review the Board’s decision on this point under
the clearly erroneous standard.
Two criteria have evolved for determining whether prior art is analogous: (1) whether
the art is from the same field of endeavor, regardless of the problem addressed, and (2) if
the reference is not within the field of the inventor’s endeavor, whether the reference still is
reasonably pertinent to the particular problem with which the inventor is involved.